traverseda
/
cpython
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

give the names of missing positional or keyword-only arguments (closes #12356)

This commit is contained in:
Benjamin Peterson 2011-06-24 09:37:26 -05:00
parent 947d6b0444
commit e109c70860
4 changed files with 212 additions and 107 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

41
Lib/inspect.py
View File

@ -918,10 +918,24 @@ def formatargvalues(args, varargs, varkw, locals,
specs.append(formatvarkw(varkw) + formatvalue(locals[varkw]))
return '(' + ', '.join(specs) + ')'
def _positional_error(f_name, args, kwonly, varargs, defcount, given, values):
def _missing_arguments(f_name, argnames, pos, values):
names = [repr(name) for name in argnames if name not in values]
missing = len(names)
if missing == 1:
s = names[0]
elif missing == 2:
s = "{} and {}".format(*names)
else:
tail = ", {} and {}".format(names[-2:])
del names[-2:]
s = ", ".join(names) + tail
raise TypeError("%s() missing %i required %s argument%s: %s" %
(f_name, missing,
"positional" if pos else "keyword-only",
"" if missing == 1 else "s", s))
def _too_many(f_name, args, kwonly, varargs, defcount, given, values):
atleast = len(args) - defcount
if given is None:
given = len([arg for arg in args if arg in values])
kwonly_given = len([arg for arg in kwonly if arg in values])
if varargs:
plural = atleast != 1
@ -980,22 +994,25 @@ def getcallargs(func, *positional, **named):
(f_name, kw))
arg2value[kw] = value
if num_pos > num_args and not varargs:
_positional_error(f_name, args, kwonlyargs, varargs, num_defaults,
num_pos, arg2value)
_too_many(f_name, args, kwonlyargs, varargs, num_defaults,
num_pos, arg2value)
if num_pos < num_args:
for arg in args[:num_args - num_defaults]:
req = args[:num_args - num_defaults]
for arg in req:
if arg not in arg2value:
_positional_error(f_name, args, kwonlyargs, varargs,
num_defaults, None, arg2value)
_missing_arguments(f_name, req, True, arg2value)
for i, arg in enumerate(args[num_args - num_defaults:]):
if arg not in arg2value:
arg2value[arg] = defaults[i]
missing = 0
for kwarg in kwonlyargs:
if kwarg not in arg2value:
if kwarg not in kwonlydefaults:
raise TypeError("%s() requires keyword-only argument %r" %
(f_name, kwarg))
arg2value[kwarg] = kwonlydefaults[kwarg]
if kwarg in kwonlydefaults:
arg2value[kwarg] = kwonlydefaults[kwarg]
else:
missing += 1
if missing:
_missing_arguments(f_name, kwonlyargs, False, arg2value)
return arg2value
# -------------------------------------------------- stack frame extraction

133
Lib/test/test_extcall.py
View File

@ -66,17 +66,17 @@ Verify clearing of SF bug #733667
>>> g()
Traceback (most recent call last):
...
TypeError: g() takes at least 1 positional argument but 0 were given
TypeError: g() missing 1 required positional argument: 'x'
>>> g(*())
Traceback (most recent call last):
...
TypeError: g() takes at least 1 positional argument but 0 were given
TypeError: g() missing 1 required positional argument: 'x'
>>> g(*(), **{})
Traceback (most recent call last):
...
TypeError: g() takes at least 1 positional argument but 0 were given
TypeError: g() missing 1 required positional argument: 'x'
>>> g(1)
1 () {}
@ -263,91 +263,80 @@ the function call setup. See <http://bugs.python.org/issue2016>.
>>> f(**x)
1 2
Some additional tests about positional argument errors:
Too many arguments:
>>> def f(a, b):
... pass
>>> f(b=1)
Traceback (most recent call last):
...
TypeError: f() takes 2 positional arguments but 1 was given
>>> def f(a):
... pass
>>> f(6, a=4, *(1, 2, 3))
Traceback (most recent call last):
...
TypeError: f() got multiple values for argument 'a'
>>> def f(a, *, kw):
... pass
>>> f(6, 4, kw=4)
Traceback (most recent call last):
...
TypeError: f() takes 1 positional argument but 2 positional arguments (and 1 keyword-only argument) were given
>>> def f(a):
... pass
>>> f()
Traceback (most recent call last):
...
TypeError: f() takes 1 positional argument but 0 were given
>>> def f(a, b):
... pass
>>> def f(): pass
>>> f(1)
Traceback (most recent call last):
...
TypeError: f() takes 2 positional arguments but 1 was given
>>> def f(a, *b):
... pass
>>> f()
TypeError: f() takes 0 positional arguments but 1 was given
>>> def f(a): pass
>>> f(1, 2)
Traceback (most recent call last):
...
TypeError: f() takes at least 1 positional argument but 0 were given
>>> def f(a, *, kw=4):
... pass
>>> f(kw=4)
TypeError: f() takes 1 positional argument but 2 were given
>>> def f(a, b=1): pass
>>> f(1, 2, 3)
Traceback (most recent call last):
...
TypeError: f() takes 1 positional argument but 0 positional arguments (and 1 keyword-only argument) were given
>>> def f(a, b=2):
... pass
>>> f()
Traceback (most recent call last):
...
TypeError: f() takes from 1 to 2 positional arguments but 0 were given
>>> def f(a, *b):
... pass
>>> f()
Traceback (most recent call last):
...
TypeError: f() takes at least 1 positional argument but 0 were given
>>> def f(*, kw):
... pass
>>> f(3, kw=4)
TypeError: f() takes from 1 to 2 positional arguments but 3 were given
>>> def f(*, kw): pass
>>> f(1, kw=3)
Traceback (most recent call last):
...
TypeError: f() takes 0 positional arguments but 1 positional argument (and 1 keyword-only argument) were given
>>> def f(*, kw, b): pass
>>> f(1, 2, 3, b=3, kw=3)
Traceback (most recent call last):
...
TypeError: f() takes 0 positional arguments but 3 positional arguments (and 2 keyword-only arguments) were given
>>> def f(a, b=2, *, kw): pass
>>> f(2, 3, 4, kw=4)
Traceback (most recent call last):
...
TypeError: f() takes from 1 to 2 positional arguments but 3 positional arguments (and 1 keyword-only argument) were given
>>> def f(a, c=3, *b, kw):
... pass
Too few and missing arguments:
>>> def f(a): pass
>>> f()
Traceback (most recent call last):
...
TypeError: f() takes at least 1 positional argument but 0 were given
>>> f(kw=3)
...
TypeError: f() missing 1 required positional argument: 'a'
>>> def f(a, b): pass
>>> f()
Traceback (most recent call last):
...
TypeError: f() takes at least 1 positional argument but 0 positional arguments (and 1 keyword-only argument) were given
>>> f(kw=3, c=4)
...
TypeError: f() missing 2 required positional arguments: 'a' and 'b'
>>> def f(a, b, c): pass
>>> f()
Traceback (most recent call last):
...
TypeError: f() takes at least 1 positional argument but 1 positional argument (and 1 keyword-only argument) were given
...
TypeError: f() missing 3 required positional arguments: 'a', 'b', and 'c'
>>> def f(a, b, c, d, e): pass
>>> f()
Traceback (most recent call last):
...
TypeError: f() missing 5 required positional arguments: 'a', 'b', 'c', 'd', and 'e'
>>> def f(a, b=4, c=5, d=5): pass
>>> f(c=12, b=9)
Traceback (most recent call last):
...
TypeError: f() missing 1 required positional argument: 'a'
Same with keyword only args:
>>> def f(*, w): pass
>>> f()
Traceback (most recent call last):
...
TypeError: f() missing 1 required keyword-only argument: 'w'
>>> def f(*, a, b, c, d, e): pass
>>> f()
Traceback (most recent call last):
...
TypeError: f() missing 5 required keyword-only arguments: 'a', 'b', 'c', 'd', and 'e'
"""
import sys

4
Misc/NEWS
View File

@ -10,6 +10,10 @@ What's New in Python 3.3 Alpha 1?
Core and Builtins
-----------------
- Issue #12356: When required positional or keyword-only arguments are not
given, produce a informative error message which includes the name(s) of the
missing arguments.
- Issue #12370: Fix super with not arguments when __class__ is overriden in the
class body.

141
Python/ceval.c
View File

@ -3046,28 +3046,118 @@ exit_eval_frame:
}
static void
positional_argument_error(PyCodeObject *co, int given, int defcount, PyObject **fastlocals)
format_missing(const char *kind, PyCodeObject *co, PyObject *names)
{
int err;
Py_ssize_t len = PyList_GET_SIZE(names);
PyObject *name_str, *comma, *tail, *tmp;
assert(PyList_CheckExact(names));
assert(len >= 1);
/* Deal with the joys of natural language. */
switch (len) {
case 1:
name_str = PyList_GET_ITEM(names, 0);
Py_INCREF(name_str);
break;
case 2:
name_str = PyUnicode_FromFormat("%U and %U",
PyList_GET_ITEM(names, len - 2),
PyList_GET_ITEM(names, len - 1));
break;
default:
tail = PyUnicode_FromFormat(", %U, and %U",
PyList_GET_ITEM(names, len - 2),
PyList_GET_ITEM(names, len - 1));
/* Chop off the last two objects in the list. This shouldn't actually
fail, but we can't be too careful. */
err = PyList_SetSlice(names, len - 2, len, NULL);
if (err == -1) {
Py_DECREF(tail);
return;
}
/* Stitch everything up into a nice comma-separated list. */
comma = PyUnicode_FromString(", ");
if (comma == NULL) {
Py_DECREF(tail);
return;
}
tmp = PyUnicode_Join(comma, names);
Py_DECREF(comma);
if (tmp == NULL) {
Py_DECREF(tail);
return;
}
name_str = PyUnicode_Concat(tmp, tail);
Py_DECREF(tmp);
Py_DECREF(tail);
break;
}
if (name_str == NULL)
return;
PyErr_Format(PyExc_TypeError,
"%U() missing %i required %s argument%s: %U",
co->co_name,
len,
kind,
len == 1 ? "" : "s",
name_str);
Py_DECREF(name_str);
}
static void
missing_arguments(PyCodeObject *co, int missing, int defcount,
PyObject **fastlocals)
{
int i, j = 0;
int start, end;
int positional = defcount != -1;
const char *kind = positional ? "positional" : "keyword-only";
PyObject *missing_names;
/* Compute the names of the arguments that are missing. */
missing_names = PyList_New(missing);
if (missing_names == NULL)
return;
if (positional) {
start = 0;
end = co->co_argcount - defcount;
}
else {
start = co->co_argcount;
end = start + co->co_kwonlyargcount;
}
for (i = start; i < end; i++) {
if (GETLOCAL(i) == NULL) {
PyObject *raw = PyTuple_GET_ITEM(co->co_varnames, i);
PyObject *name = PyObject_Repr(raw);
if (name == NULL) {
Py_DECREF(missing_names);
return;
}
PyList_SET_ITEM(missing_names, j++, name);
}
}
assert(j == missing);
format_missing(kind, co, missing_names);
Py_DECREF(missing_names);
}
static void
too_many_positional(PyCodeObject *co, int given, int defcount, PyObject **fastlocals)
{
int plural;
int kwonly_given = 0;
int atleast = co->co_argcount - defcount;
int i;
PyObject *sig, *kwonly_sig;
if (given == -1) {
given = 0;
for (i = 0; i < co->co_argcount; i++)
if (GETLOCAL(i))
given++;
}
assert((co->co_flags & CO_VARARGS) == 0);
/* Count missing keyword-only args. */
for (i = co->co_argcount; i < co->co_argcount + co->co_kwonlyargcount; i++)
if (GETLOCAL(i))
if (GETLOCAL(i) != NULL)
kwonly_given++;
if (co->co_flags & CO_VARARGS) {
plural = atleast != 1;
sig = PyUnicode_FromFormat("at least %d", atleast);
}
else if (defcount) {
if (defcount) {
int atleast = co->co_argcount - defcount;
plural = 1;
sig = PyUnicode_FromFormat("from %d to %d", atleast, co->co_argcount);
}
@ -3089,6 +3179,7 @@ positional_argument_error(PyCodeObject *co, int given, int defcount, PyObject **
else {
/* This will not fail. */
kwonly_sig = PyUnicode_FromString("");
assert(kwonly_sig != NULL);
}
PyErr_Format(PyExc_TypeError,
"%U() takes %U positional argument%s but %d%U %s given",
@ -3217,16 +3308,18 @@ PyEval_EvalCodeEx(PyObject *_co, PyObject *globals, PyObject *locals,
SETLOCAL(j, value);
}
if (argcount > co->co_argcount && !(co->co_flags & CO_VARARGS)) {
positional_argument_error(co, argcount, defcount, fastlocals);
too_many_positional(co, argcount, defcount, fastlocals);
goto fail;
}
if (argcount < co->co_argcount) {
int m = co->co_argcount - defcount;
for (i = argcount; i < m; i++) {
if (GETLOCAL(i) == NULL) {
positional_argument_error(co, -1, defcount, fastlocals);
goto fail;
}
int missing = 0;
for (i = argcount; i < m; i++)
if (GETLOCAL(i) == NULL)
missing++;
if (missing) {
missing_arguments(co, missing, defcount, fastlocals);
goto fail;
}
if (n > m)
i = n - m;
@ -3241,6 +3334,7 @@ PyEval_EvalCodeEx(PyObject *_co, PyObject *globals, PyObject *locals,
}
}
if (co->co_kwonlyargcount > 0) {
int missing = 0;
for (i = co->co_argcount; i < total_args; i++) {
PyObject *name;
if (GETLOCAL(i) != NULL)
@ -3254,9 +3348,10 @@ PyEval_EvalCodeEx(PyObject *_co, PyObject *globals, PyObject *locals,
continue;
}
}
PyErr_Format(PyExc_TypeError,
"%U() requires keyword-only argument '%S'",
co->co_name, name);
missing++;
}
if (missing) {
missing_arguments(co, missing, -1, fastlocals);
goto fail;
}
}